This project was begun during this fiscal year. The purpose of the project is to compare methods of analysis among different groups of investigators who all attend the Genetic Analysis Workshop. Previously published data collected by other investigators in locally IRB-approved studies are supplied to workshop participants without access to personal identifiers. These anonymized data are then analyzed by each group of investigators participating in the workshop, results are submitted and presented at the workshop and then published as refereed papers as part of the Proceedings of the workshop. The specific aims of the project are to 1) compare the conclusions about linkage analysis of a major gene for bipolar disease among the different data sets; 2) compare the performance of several different methods of linkage analysis on the same data.